Goodwill and Identified Intangible Assets - Summary of Goodwill and Identified Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Apr. 03, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	210,343	$ 210,343
Accumulated Amortization	(201,651)	(199,744)
Total future amortization expense	8,692us-gaap_FiniteLivedIntangibleAssetsNet	10,599us-gaap_FiniteLivedIntangibleAssetsNet
Developed core technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	136,145	136,145
Accumulated Amortization	(135,887)	(135,426)
Total future amortization expense	258	719
Developed core technology [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life	4 years
Developed core technology [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life	6 years
Customer relationships/contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	67,098	67,098
Accumulated Amortization	(60,001)	(58,784)
Total future amortization expense	7,097	8,314
Customer relationships/contracts [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life	5 years
Customer relationships/contracts [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life	6 years
Maintenance agreements and related relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,100	7,100
Accumulated Amortization	(5,763)	(5,534)
Total future amortization expense	1,337	$ 1,566
Maintenance agreements and related relationships [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life	6 years
Maintenance agreements and related relationships [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life	7 years

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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